Hippo fossil trail
It seemed to be a rough dirt road leading to nowhere. But these are the the remains of hippo trails leading to dried-up wallowing pools in a remote part of Tanzania. Hippos wallow in freshwater pools during the day to escape the sun. At night they plow through the mud to grasslands to eat. Geologist Daniel Deocampo, who first came across these paths also found similar paths near Olduvai Gorge, where some of the oldest hominid fossils have been found. He spied a U-shaped trench four and a half feet wide and four and a half feet deep embedded in 1.75-million-year-old sediments that had been excavated in 1995. Deocampo identified the trench as a fossil hippo trail.